From 1cd45889fa225e0c49da5c9cd695a5706ebc5583 Mon Sep 17 00:00:00 2001
From: Jakob Botsch Nielsen <jakob.botsch.nielsen@gmail.com>
Date: Sat, 31 Jan 2026 14:23:47 +0100
Subject: [PATCH 1/3] Avoid async thunks in `RuntimeHelpers.PrepareMethod`

This function should JIT the method that has the user IL.
---
 src/coreclr/vm/reflectioninvocation.cpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/coreclr/vm/reflectioninvocation.cpp b/src/coreclr/vm/reflectioninvocation.cpp
index 461dbf1a4a1d01..65c4c0fdde3c1b 100644
--- a/src/coreclr/vm/reflectioninvocation.cpp
+++ b/src/coreclr/vm/reflectioninvocation.cpp
@@ -1283,6 +1283,11 @@ static void PrepareMethodHelper(MethodDesc * pMD)
 
     pMD->EnsureActive();
 
+    if (pMD->IsAsyncThunkMethod())
+    {
+        pMD = pMD->GetAsyncVariant();
+    }
+
     if (pMD->ShouldCallPrestub())
         pMD->DoPrestub(NULL);
 

From ef1227eba8a989c846e21679d09ae76acaab7e6f Mon Sep 17 00:00:00 2001
From: Jakob Botsch Nielsen <jakob.botsch.nielsen@gmail.com>
Date: Sat, 31 Jan 2026 15:14:34 +0100
Subject: [PATCH 2/3] Use Jan's suggestion

---
 src/coreclr/vm/reflectioninvocation.cpp | 16 +++++++++-------
 1 file changed, 9 insertions(+), 7 deletions(-)

diff --git a/src/coreclr/vm/reflectioninvocation.cpp b/src/coreclr/vm/reflectioninvocation.cpp
index 65c4c0fdde3c1b..7490f4870befd5 100644
--- a/src/coreclr/vm/reflectioninvocation.cpp
+++ b/src/coreclr/vm/reflectioninvocation.cpp
@@ -1283,20 +1283,22 @@ static void PrepareMethodHelper(MethodDesc * pMD)
 
     pMD->EnsureActive();
 
-    if (pMD->IsAsyncThunkMethod())
+    if (pMD->IsWrapperStub())
     {
-        pMD = pMD->GetAsyncVariant();
+        if (pMD->ShouldCallPrestub())
+            pMD->DoPrestub(NULL);
+        pMD = pMD->GetWrappedMethodDesc();
     }
 
-    if (pMD->ShouldCallPrestub())
-        pMD->DoPrestub(NULL);
-
-    if (pMD->IsWrapperStub())
+    if (pMD->IsAsyncThunk())
     {
-        pMD = pMD->GetWrappedMethodDesc();
         if (pMD->ShouldCallPrestub())
             pMD->DoPrestub(NULL);
+        pMD = pMD->GetAsyncVariant();
     }
+
+    if (pMD->ShouldCallPrestub())
+        pMD->DoPrestub(NULL);
 }
 
 // This method triggers a given method to be jitted. CoreCLR implementation of this method triggers jiting of the given method only.

From 03d794ba644788439c7a5eba4ea7c1273b316b2f Mon Sep 17 00:00:00 2001
From: Jan Kotas <jkotas@microsoft.com>
Date: Sat, 31 Jan 2026 09:40:49 -0800
Subject: [PATCH 3/3] Update src/coreclr/vm/reflectioninvocation.cpp

---
 src/coreclr/vm/reflectioninvocation.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/coreclr/vm/reflectioninvocation.cpp b/src/coreclr/vm/reflectioninvocation.cpp
index 7490f4870befd5..ed82fba96fb8c4 100644
--- a/src/coreclr/vm/reflectioninvocation.cpp
+++ b/src/coreclr/vm/reflectioninvocation.cpp
@@ -1290,7 +1290,7 @@ static void PrepareMethodHelper(MethodDesc * pMD)
         pMD = pMD->GetWrappedMethodDesc();
     }
 
-    if (pMD->IsAsyncThunk())
+    if (pMD->IsAsyncThunkMethod())
     {
         if (pMD->ShouldCallPrestub())
             pMD->DoPrestub(NULL);